1. Field of the Invention
This invention relates to an elastomeric bearing, and more particularly to an elastomeric bearing for use in motor vehicles. Such bearings typically have at least two fastening parts which can be connected to one another by means of an elastomer spring. In addition, there can also be a vertically acting hydraulic damping apparatus and at least one hydraulic damping apparatus acting in at least one horizontal direction. The damping apparatus, in general, will comprise chambers filled with damping fluid, while the chambers can be connected to one another by means of damping passages.
2. Background Information
Known elastomeric bearings typically have, as discussed above, two fastening parts which are connected to one another by means of an elastomer spring, and also include a hydraulic damping apparatus. In the elastomeric bearing as disclosed by German Patent No. 30 24 090, the elastomer spring is divided by the fluid chambers into an outer, one-piece, or multi-piece thrust spring, and an inner, ring-shaped elastomeric spring. The inner spring will generally be in contact with the fastening part by means of a base body. As a result of this configuration, only a small proportion of the bearing load is absorbed by the inner ring-shaped elastomeric spring, and a damping of the low-frequency vibrations in the vertical direction is achieved. One disadvantage of a bearing of this type is that no damping can take place in the soft thrust direction. Thus, on account of the soft small spring constants of the elastomer spring, large, undamped movements are possible, and unstable resonance vibrations can occur.
Another known bearing in which the fastening parts are connected to one another by means of an elastomer spring is disclosed by European Patent No. 0 042 761. This elastomeric bearing is equipped with one damping apparatus which acts in the horizontal direction and one which acts in the vertical direction. A disadvantage of this configuration is that the simple embodiment is only somewhat effective.